When these names first became attached to some of the Atlantic islands is uncertain. Diodorus Siculus does not apply either term to the island discovered by the Carthaginians, and described by him in phrases applicable to both. The two islands described by sailors to Sertorius about 80 B.C. were depicted in colors which reminded Plutarch of the Isles of the Blessed, and it is certain that toward the close of the republic the name _Insulae Fortunatae_ was given to certain of the Atlantic islands, including the Canaries. In the time of Juba, king of Numidia, we seem to distinguish at least three groups, the _Insulae Fortunatae_, the _Purpurariae_, and the _Hesperides_, but beyond the fact that the first name still designated some of the Canaries identification is uncertain; some have thought that different groups among the Canaries were known by separate names, while others hold that one or both of the Madeira and Cape de Verde groups were known.[297] The Canaries were soon lost out of knowledge again, but the Happy or Fortunate Islands continued to be an enticing mirage throughout the Middle Ages, and play a part in many legends, as in that of St. Brandan, and in many poems.[298] Beside these ancient, widespread, popular myths, embodying the universal longing for a happier life, we find a group of stories of more recent date, of known authorship and well-marked literary origin, which treat of western islands and a western continent. The group comprises, it is hardly necessary to say, the tale of Atlantis, related by Plato; the fable of the land of the Meropes, by Theopompus; and the description of the Saturnian continent attributed to Plutarch.